Centrifugal pump primer



W im 19% B. SKIDMORE CENTRIFUGAL PUMP PRIMER Filed May' 8,l 1953 I m/@wtor mmnmmmnmma Patented Mar. 10, 1936 UNITED STATES PATENT OFFICE 2,033,744 CENTRIFUGAL PUMP PRIMER Benjamin Skidmore, St. Joseph, Mich.

Application May 8, A1933, Serial No. 669,903

7 Claims. (Cl. 103--113) This invention relates to improvements in centrifugal pump primer, and one of the objects of the same is to provide improved means whereby a centrifugal pump may be primed by removing the air from the pump casing and suction pipe by means of a vacuum producing apparatus.

To the attainment of these ends and the accomplishment of other new and useful objects as will appear, the invention consists in the features of novelty in substantially the construction, combination and arrangement of the several p-arts hereinafter more fully described and claimed and shown in the accompanying drawing illustrating this invention, and in which Figure l is a view partly in elevation, partly in section, and with parts broken away, showing the application of the invention to a typical vacuum and boiler feed unit as used in vacuum steam heating systems.

Figure 2 is a detail vertical sectional view taken on line 2 2, Figure 1,

While in the drawing there is illustrated a unit where the vacuum and boiler feed pump are mounted upon an accumulator tank to which the return lines run from the heating system, it is to be understood that the unit may be arranged in any other suitable manner.

Referring more particularly to the drawing, the numeral l0 designates an accumulator or receiving tank of any desired size and configuration, and into which tank the return line II from the system discharges.

Supported by the tank is a vacuum pump I2 which may be of the well known construction, and the numeral I3 designates a centrifugal pump.

A suction pipe I4 extending into the tank I0 for any desired distance, but preferably terminating adjacent the bottom of the tank, leads to the centrifugal pump I3, and a suction pipe I5 from the vacuum pump I2 has communication with the tank I0 at the upper part thereof.

Arranged within the suction pipe I5 is a check valve I5 of any desired or suitable construction, and leading from the suction line preferably from 'the pipe I5 to the top of the suction pipe I4 of the centrifugal pump, is a pipe Il, of a comparatively small diameter. v

Within the tank I0 is a float I8 which operates with the rise and fall of the water level in the 0 tank, and this float Is during its rising and fauing movements, will control a stopping and starting switch for the unit (not shown). 'Ihe float I8 also controls a valve I9.

This valve I9 is arranged adjacent the inlet of the pipe I5 and may be of any desired or suitable construction which will operate when the float rises to close or partially close the inlet 0f the pipe I5, and when the float is lowered, the valve I9 will open the inlet of the pipe I5 which leads to the vacuum pump from the tank. 5

An overflow 28 is also provided leading from the casing of the vacuum pump I2 to the tank I 0, so as to allow water to escape from the pump casing I2 to be delivered into the tank I0.

Within the pipe 2|] is arranged a trap 2|, in 10 which a. float 22 operates. This float 22 will operate to permit water to pass, but will close to prevent air from owing therethrough.

The numeral 23 designates the discharge outlet of the centrifugal pump and 24 designates the dis- 15 charge outlet of the vacuum pump.

Any form of connection may be provided between the oat I8 and the valve I9, but there is preferably provided spaced collars 25-26 secured to the stem 21 of the valve and the stem passes 20 through the arm 28 to which the float I8 is secured. Obviously the collars may be adjusted to any desired extent so as to vary the time in the cycle of operation in which the float will operate the valve, according to the liquid level that it is 25 desired to establish in the tank I0.

In operation and when water accumulates in the tank I8 to a predetermined height (regardless of the degree of vacuum in the tank and return lines) the float I8 will actuate the oat con- 30 trolled switch (not sho-wn) and which latter controls the motor, to start the pump.

The valve I9 Will then be closed, causing a higher vacuum to be created in the pipe I5 than in the tank Ill, which will result in the air being drawn 35 through the pipe II from the casing of the centrifugal pump I3 and the suction pipe I4, being displaced with water drawn up from the tank I8, thus priming the centrifugal pump I3.

When the centrifugal pump is once primed, it 40 will continue to operate until the water line in the tank I0 lowers sufliciently to uncover the lower end of the suction pipe I4. When the suction pipe I4 is uncovered, the centrifugal pump will 45 of course lose its priming.

As soon as the centrifugal pump starts to operate, the water line in the tank Ill will lower quickly, causing the float I8 to drop, with the result that the valve I9 will be opened, thereby allowing 50 the vacuum pump I2 to withdraw air and vapor from the tank Ill through the pipe I5. It is only necessary that the valve I9 shall partially close the inlet end of the pipe I5 suiciently to cause difference in vacuum to raise the water from the 2 P l n 2,033,744

tank I0 through the pipe I 4 to prime the centrifugal pump.

Just before the centrifugal pump is supplied with its full prime, a small quantity of water will be drawn through the pipe l1 by the vacuum pump, thus insuring its necessary operating water.

Should an excess of water be drawn into the Vacuum pump, it will flow through the overflow pipe 2D to the tank I0, the trap 2| and float 22 operating to allow only water to pass into the tank I0 from the pipe 20.

While the preferred form of the invention has been herein shown and described, it is to be understood that various changes may be made in the details of construction and in the combination and arrangement of the several parts, within the scope of the claims, without departing from the spirit of this invention.

What is claimed as new is:-

1. In combination with a Vacuum and boiler feed unit embodying ,a Water pump and an air pump, an accumulator tank adapted to be placed under vacuum, an air pipe leading from the tank to the air pump, a suction pipe leading from said tank to the water pump, means embodying .a valve for controlling the flow of air to the air pump, a float within the tank for controlling said Valve and also for controlling the starting and stopping of the unit, the said control of the flow of air to the air pump operating to cause ,a higher degree of suction to be manifested in the water pump and said suction pipe than in said tank, thereby causing water to flow through said suction pipe to prime the Water pump, a water overflow pipe leading from the air pump to said tank, and means for controlling the flow of fluid through said overflow pipe.

2. In combination with a Vacuum and boiler feed unit embodying a water pump and an air pump, an accumulator tank .adapted to be placed under vacuum, an air pipe leading from the tank to the air pump, a suction pipe leading from said tank to the Water pump, means embodying a valve, and a float located Within the accumulator tank for controlling the operation of the valve to restrict the flow of air to the air pump, means whereby-the restriction of said flow of air to the air pump will cause a higher degree of suction to be manifested in the water pump and said suction pipe than in said tank, thereby causing water to ilow through said suction pipe to prime the water pump, a water overow pipe leading from the air pump to the tank, a trap in the overflow pipe, and a float in the trap operating automaticallly to permit only water to pass to the tank.

3. In combination with a vacuum and boiler feed unit embodying a water pump and an air pump, an accumulator tank adapted to be placed under vacuum, an ,air pipe leading from the tank, to the air pump, a water supply suction pipe leading from the tank to the water pump, a float controlled Valve for controlling the supply of air from the tank to the air pump, a restricted communication between the water pump and said air pipe whereby when the supply of air to the air pump is restricted. the degree of vacuum in the air pipe will be increased above the Vacuum in said tank to cause water to be drawn from said tank through said suction pipe to prime the water pump, an overflow pipe leading from the air pump to the tank, and a float trap in the overflow pipe and operating to permit only water to flow to the tank.

4. In combination with a vacuum and boiler feed unit embodying a water pump and an air pump, an accumulator tank adapted to be placed under vacuum, an air pipe leading from the tank to the air pump, a water supply suction pipe leading from the tank to the water pump, a float controlled valve for controlling the supply of air from the tank to the air pump, a restricted communication between the water pump and said air pipe, and a check Valve in the air pipe between the point of connection of the said restricted communication therewith `and the air pump, said restricted communication operating when the supply of air to the air pump is restricted in the said air pipe, to cause the suction in the air pipe to be increased above the vacuum in said tank to cause water to be drawn from said tank through said water suction pipe to prime the water pump.

5. In combination with a vacuum and boiler feed unit embodying a water pump and an air pump, an accumulator tank adapted to be placed under vacuum, an air pipe leading from the tank to the air pump, a water supply suction pipe leading from the tank to the water pump, a float controlled valve for controlling the supply of air from the tank to the air pump, a restricted communication between the water pump and said air pipe whereby when the supply of air to the air pump is restricted the degree of vacuum in the air pipe will be increased above the vacuum in said tank to cause water to be drawn from said tank through said suction pipe to prime the water pump, means for supplying make up water to the air pump, an overow pipe leading from the air pump to the tank, and a float trap in the overflow pipe and operating to permit only water to flow to the tank.

6. In combination with a vacuum and boiler feed unit embodying a water pump and an air pump, an accumulator tank adapted to be placed under vacuum, an air pipe leading from the tank to the air pump, a water supply suction pipe leading from the tank to the water pump, a float controlled valve for controlling the supply of air to the air pump, a restricted communication between the water pump and said air pipe, a check Valve in the air pipe between the point of connection of said restricted communication therewith and the air pump, said restricted communication operating when the supply of air to the air pump is restricted in said air pipe, to cause the suction in the air pipe to be increased above the vacuum in said tank to cause water to be drawn from said tank through said water suction pipe to prime the pump, and means for supplying make up water to the pump.

'7. In combination with a vacuum and boiler feed unit embodying a water pump and an air pump, an accumulator tank adapted to be placed under vacuum, an air pipe leading from the tank to the air pump, a suction pipe leading from the said tank to the water pump, means embodying a valve for controlling the flow of air to the air pump, a oat within the tank for controlling said valve and for also controlling the stopping and starting of the unit, the said control of the flow of air to the air pump operating to cause a higher degree of suction to be manifested in the water pump and said suction pipe than in the tank, thereby causing water to ow through said suc` tion pipe to prime the water pump, and an overow pipe leading from the air pump to said tank.

BENJAMIN SKIDMORE. 

